反应详情

The procedure described for 5c was used. Deprotection of 100 mg of 5a and coupling with 95 mg of (2S)-[[(phenylmethyl)sulfonyl]amino]butanedioic acid 4-(1,1-dimethylethyl)ester (prepared from Asp(OtBu)-OH and phenylmethylsulfonylchloride using the procedure described for 5b) yielded the title compound (133 mg) as a mixture of diastereomers (1:1). 1H-NMR 400 MHz (CD3OD) δ: 0.83-1.69 (6H, m), 1.41 and 1.42 (9H, 2× s), 2.42-2.63 (2H, m), 3.09-3.61 (6H, m), 4.01-4.38 (3H, m), 5.22-5.31 (1H, m), 7.13-7.80 (9H, m), 8.25-8.30 (1H, m).